Billet-casting



R. E. BRADLEY.

BILLET CASTING. APPLICATION FILED MAR 20, 1920.

Inventor 0 Brad J @1 5 1066/27 mw w UNITED STATES ROSS EDWARD BRADLEY, 0F ROLAND PARK, MARYLAND BILLET-CASTING.

Specification of Letters Patent.

Patented Oct. 11, 1921.

Application filed March 20, 1920. Serial No. 367,525.

To (ZZZ whom it may concern:

Beit known that 1, Ross EDWARD Bunn- LnY, a citizen of the United States, residing at Roland Park, in the county of timore, State of lilaryland, have invented a new and useful Billet-Casting, of which the following is a specification.

My invention relates to improvements in billet casting. The object is to provide in proved method and means for casting a. hollow or pproximately hollow cylindrical metal billet.

The invention is especially applicable to casting billets of copper, or the alloys thereof, for use in tube drawing.

The invention contemplates the elimination of the sand core and the substitution of a metallic core so devised and arranged as to yield to the pressure of the surrounding billet, due to its contraction in cooling, in order to prevent the cracking or breaking of the billet, as would ordinarily be the case were the billet allowed to cool and contract about a rigid metallic core.

Referring to the drawings, which illustrate merely by way of example, suitable means for effecting my invention Figure 1 is a vertical section of a mold and core embodying my invention, in position for casting.

r 1g. 2 is an elevation or tne core which is preferably of sheet metal.

Fig. 3 is a horizontal section on line 3 -3 ig. 2. lig. 4? is a sectional elevation of a mold provided with another form of collapsible core embodying my invention.

Pig. 5 is a cross-section of the core shown in Fig. l.

Similar numerals refer to similar parts throughout the several views.

As shown in Figs. 1 and 4;, the mold 10 is suitably supported on the trunions 11 and is provided at the top with the pouring cup 12, and at the bottom with the block or core bit 13, which serves to close the bottom of the mold. and to centralize the lower end of the core 14:. Suitable means, such as pin 15, is provided for holding the block 13 in position during the molding operation.

The pouring cup 12 is provided with the apertures 16 arranged around the upper end of the mold for'permittingthe flow of metal from the cup into the mold.

In Figs. 1, 2 and 3, the core 1% consists of a flexible sheet metal cylinder, having its side edges or margins 17 and 18 adapted to overlap. The lower end of this sheet metal core rests in the countersunk portion of block 18, the outer margin of said countersunlr portion forming means for limiting the expanding movement 01' the said core. This supporting block in no way interferes with the tree contraction of the core, due to the contraction of the metal, as it cools. In

like manner the spaced lugs or projections 12, extending radially from the inner wall of the lower flange of tunnel member 12, engage tne upper periphery of the core, to limit its expanding movement at this end, without interfering with its free contraction.

In operation, with a device as shown in Figs. 1., 2 and 3, the billet is cast by pouring the metal into the cup 12, and through the aperture 16, until the moldhas been filled to approximately the 'level ot' saidsuitable way.

In the structure shown in Figs. 41 and 5 the mold and pouring cup are substantially the same, while the core is composed of the elements 21, 22 and 23. These elements have the relative crosssection substantially as shown in Fig. 5. The middle element 22 is wedge shaped, and is provided with the feathers or ridges 24L, seated in corresponding grooves in the elements 21 and 2:5, for maintaining the said three elements in required relative cross-sectional position. It will be understood that the elements 21 and 23 are correspondingly tapered to accommodate the tapered formation of the wedge 22, so that when the wedge 22 is in the position shown in Fig. 4:, the said elements will form a substantially cylindrical core. The middle or wedge element 22 is held in operative position by means of the pin 25 at the top of the pouring cup.

it will also be noted that in the structure shown in Fig. i, the block or core bit 13 1s counter-sunk to provide a seat for the outer elements 21 and 23 f the core, and to form a element 22, while the other elements 21 and 28 are still held in place by said block.

lVhen the mold has been filled with molten metal as described in connection with Figs. 1, 2 and 3, and the billet has become sufficiently set, the pin 25 is withdrawn. and the wedge 22 is-depressed so as to permit a collapse or moving toward each other of the elements 21 and 23. his serves to allow the contraction of the billet, due to its cooling, without danger of splitting the same.

When the billet has sutliciently cooled and contracted the wedge 22 may be moved tan ther downwardly, or entirely removed from the elements 21 and 23, whereupon the elements 21 and 23 may be ejected or withdrawn from the billet.

In other respects the operation is substantially the same as that described with respect to Figs. 1, 2 and 3.

What I claim is I 1. The method of casting a hollow billet for use in tube drawing whichconsists in pouring the molten metal into a mold about a resilient metallic core supported vertically on one of its ends and restrained as to its two ends so that it cannot expand beyond a predetermined maximum but will freely yield to the pressure of the surrounding casting as to its periphery to an extent corresponding to the contraction of the billet upon cooling, and, after the metal of the bills has sulficiently set, removing said billet from the mold with the core therein.

2. In a device or" the character described, the combination of an approximately cylindrical mold, a vertically arranged resilient metallic core placed centrally therein, means for supporting the core at itslower end and means for restraining said core as to its two entremities so that it cannot expand beyond a predetermined maximum but will freely yield to the pressure of the surrounding casting to an extent corresponding to the contraction of the billet upon cooling, the parts arranged and proportioned so that the billet with the core inclosed therein may be re moved from the mold after the metal of the billet has sufiiciently set. I

3. T he combination of a cylindrical vertically arranged metallic mold, a pouring funnel removably positioned on the top of said mold, a block removably secured within the mold near the bottom thereof, a core, adapted to contract with the contracting metal of the casting, secured within the mold and means including lugs projecting redially from the tunnel for limiting the expanding movement of said core.

ROSS EDNARD BRADLEY. 

